Petunia illustration

Growing Petunia in Zone 11b

Zone 11b has a year-round growing season. Petunia can be planted almost any time with proper planning. Last frost: Jan 15. First frost: Dec 31.

Planting Calendar

Indoor
Outdoor
Harvest
Nov 6Dec 31

Season: Jan 15 – Dec 31 (350 days)

Zone11b
Last FrostJan 15
First FrostDec 31
Season Length350 days
Days to Harvest60
SunFull Sun
Frost ToleranceNone
Spacing10/sqft

When to Plant Petunia in Zone 11b

Start Seeds Indoors: Nov 6

Start Petunia seeds indoors around Nov 6 (10 weeks before last frost). Optimal germination temperature: 75°F. Germinates in 7–14 days.

Transplant Outdoors: Jan 22

Transplant Petunia seedlings outdoors after Jan 22. Wait until soil temperature reaches 60°F. Space plants at 10/sqft. Harden off plants for a week before moving outside.

Harvest: Mar 8

First harvest approximately Mar 8 (~45 days from transplant). Continue harvesting until first frost (Dec 31).

Frequently Asked Questions

When should I plant Petunia in Zone 11b?

Start Petunia seeds indoors around Nov 6. Transplant outdoors after Jan 22. Expect first harvest around Mar 8.

What is the last frost date for Zone 11b?

The average last spring frost date for Zone 11b is Jan 15. The first fall frost averages Dec 31, giving a 350-day growing season.

Can I grow Petunia in Zone 11b?

Yes. Petunia needs 60 days to harvest. Zone 11b has a 350-day growing season, which is sufficient.

What is the best month to plant Petunia in Zone 11b?

The best time to start Petunia in Zone 11b is Nov. Begin seeds indoors around Nov 6, then transplant outdoors after the last frost date of Jan 15.

How long does Petunia take to harvest?

Petunia takes approximately 60 days from planting to harvest. In Zone 11b, expect your first harvest around Mar 8.

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